Use your head!
"... test all things..." 1 Thessalonians 5.21
Thomas Aquinas was another luminary to emerge out of the Dark Ages. His thinking was inspired by Aristotle's empirical approach: that the way we understand life should be based on observation rather than by theorising. This led him to two particularly influential insights into our understanding of the world and of God.
Noticing that everything happens (or moves) as a result of something else causing (or pushing) it, Aquinas deduced that something (or someone) must have initiated the process: "the unmoved mover". He concludes that this must be God. And, when one further examines the extraordinarily complex yet effective way in which everything in the universe and on planet earth conspire together to support life, that too argues for an intelligent and very powerful creator.
Aquinas's observations are known as the cosmological and teleological arguments for the existence of God. Not everyone agrees with his conclusions, of course, but his logic is sound and has established the scientific credibility for belief in God.
Should this matter? Does God depend on our ability to "prove" his existence? Not really but he has called us to be his witnesses, to make disciples and to use of our gifts. So to live faithfully must include using our heads, as well as our hearts and hands...